vmm: Add iommu field to the VmConfig

Adding a simple iommu boolean field to the VmConfig structure so that we
can later use it to create a virtio-iommu device for the current VM.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

vmm/src/api/openapi/cloud-hypervisor.yaml

@@ -176,6 +176,9 @@ components:
             $ref: '#/components/schemas/VhostUserBlkConfig'
         vsock:
           $ref: '#/components/schemas/VsockConfig'
+        iommu:
+          type: boolean
+          default: false
       description: Virtual machine configuration
 
     CpuConfig:

vmm/src/config.rs

@@ -669,6 +669,8 @@ pub struct VmConfig {
     pub vhost_user_net: Option<Vec<VhostUserNetConfig>>,
     pub vhost_user_blk: Option<Vec<VhostUserBlkConfig>>,
     pub vsock: Option<Vec<VsockConfig>>,
+    #[serde(default)]
+    pub iommu: bool,
 }
 
 impl VmConfig {
@@ -677,6 +679,8 @@ impl VmConfig {
     }
 
     pub fn parse(vm_params: VmParams) -> Result<Self> {
+        let iommu = false;
+
         let mut disks: Option<Vec<DiskConfig>> = None;
         if let Some(disk_list) = &vm_params.disks {
             let mut disk_config_list = Vec::new();
@@ -778,6 +782,7 @@ impl VmConfig {
             vhost_user_net,
             vhost_user_blk,
             vsock,
+            iommu,
         })
     }
 }